Automotive fuel system seals include polymeric, deformable components that are widely used in many different applications to make a pressure-tight joint between parts, and typically include ring-shaped axial seals and radial seals or O-rings. In use, radial seals are compressed in a radial direction perpendicular to a seal centerline on opposed radially inside and outside surfaces of the radial seal's cross section, whereas axial seals are compressed in an axial direction parallel to a seal centerline on axially opposed surfaces of the axial seal's cross section.
Axial seals are widely used to seal openings of containers. For example, axial seals are often used to seal an opening in a fuel tank and are disposed in a flange-type joint between a mounting flange of a fuel delivery module and an outer surface of the fuel tank.